The invention relates to the field of
magnesium alloy, in particular to a preparation method of a comprehensive protective wave-absorbing
coating on the surface of
magnesium alloy and various coatings prepared by the method. The wave-absorbing
coating is coated on a micro-arc oxidized
ceramic layer on the surface of the
magnesium alloy, so that the comprehensive
coating which is good in
corrosion resistance and in wave-absorbing functionality can be prepared. The invention adopts a
magnesium alloy micro-arc oxidation technology and a wave-absorbing coating composite technology, the stable micro-arc oxidation technology is carried out in case of large area by the
magnesium alloy micro-arc oxidation technology, and a
ceramic layer with a compact
microstructure is prepared, so that the
corrosion resistance of the
magnesium alloy can be obviously improved. The wave-absorbing coating composite technology can be used for sealing the
ceramic layer, so that the
corrosion resistance of the ceramic layer can be further improved, and the ceramic layer has the function of
wave absorption as well. The comprehensive coating provided by the invention has the characteristics of being good in corrosion resistance, wide in electromagnetic wave absorbing frequency range, high in
absorption rate, firm in
surface bonding and the like, is widely applicable to the fields such as
aviation,
aerospace, war industry and electronic products, and is high in social value and economic value.